<!DOCTYPE HTML>
<html>
<head>
  <title>Test whether an audio file played with a volume set to 0 plays silence</title>
  <script type="text/javascript" src="/tests/SimpleTest/SimpleTest.js"></script>
  <link rel="stylesheet" type="text/css" href="/tests/SimpleTest/test.css" />
</head>
<body>
<audio preload=none src="ting-48k-1ch.ogg" controls> </audio>
<script>
  SimpleTest.waitForExplicitFinish();

  var count = 20;

  function isSilent(b) {
    for (var i = 0; i < b.length; b++) {
      if (b[i] != 0.0) {
        return false;
      }
    }
    return true;
  }

  var a = document.getElementsByTagName("audio")[0];
  a.volume = 0.0;
  var ac = new AudioContext();
  var measn = ac.createMediaElementSource(a);
  var sp = ac.createScriptProcessor();

  sp.onaudioprocess = function(e) {
    var inputBuffer = e.inputBuffer.getChannelData(0);
    ok(isSilent(inputBuffer), "The volume is set to 0, so all the elements of the buffer are supposed to be equal to 0.0");
  }
  // Connect the MediaElementAudioSourceNode to the ScriptProcessorNode to check
  // the audio volume.
  measn.connect(sp);
  a.play();

  a.addEventListener("ended", function() {
    sp.onaudioprocess = null;
    SimpleTest.finish();
  });

</script>
</body>
</html>
